This invention provides a quantum dot with excellent stability which comprises a M1C1core made of a first formula of M1C1, and a plurality of M2C2inner shells made of a second formula of M2C2. Said M1C1core includes a surface having a first family of crystallographic planes with a plurality of crystallographic planes and all non-oxidized crystal planes, and a second family of crystallographic planes with a plurality of crystallographic planes and all oxidized crystal planes. Each of said M2C2inner shells growth on a corresponding one of each of said crystallographic planes of said first family of crystallographic planes of said core. M1 is at least one of element selected form the group consisting of Al, Ga, and In, and C1 is at least one of element selected form the group consisting of P, and As. M2 is at least one of element selected form the group consisting of Zn, Pb, Ag, Cu, Mn, Cd, and Mg, and C2 is at least one of element selected form the group consisting of S, Se, O, F, Cl, Br, I, and Te. |